Commit f11cc2af authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

PCI/MSI: Switch msi_capability_init() to guard(msi_desc_lock) 



Split the lock protected functionality of msi_capability_init() out into a
helper function and use guard(msi_desc_lock) to replace the lock/unlock
pair.

No functional change intended.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/all/20250319105506.504992208@linutronix.de
parent 5c0ba4f9

drivers/pci/msi/msi.c

+36 −32
Original line number Diff line number Diff line
@@ -335,38 +335,13 @@ static int msi_verify_entries(struct pci_dev *dev) 
	return !entry ? 0 : -EIO;

}



/**

 * msi_capability_init - configure device's MSI capability structure

 * @dev: pointer to the pci_dev data structure of MSI device function

 * @nvec: number of interrupts to allocate

 * @affd: description of automatic IRQ affinity assignments (may be %NULL)

 *

 * Setup the MSI capability structure of the device with the requested

 * number of interrupts.  A return value of zero indicates the successful

 * setup of an entry with the new MSI IRQ.  A negative return value indicates

 * an error, and a positive return value indicates the number of interrupts

 * which could have been allocated.

 */

static int msi_capability_init(struct pci_dev *dev, int nvec,

			       struct irq_affinity *affd)

static int __msi_capability_init(struct pci_dev *dev, int nvec, struct irq_affinity_desc *masks)

{

	int ret = msi_setup_msi_desc(dev, nvec, masks);

	struct msi_desc *entry, desc;

	int ret;



	/* Reject multi-MSI early on irq domain enabled architectures */

	if (nvec > 1 && !pci_msi_domain_supports(dev, MSI_FLAG_MULTI_PCI_MSI, ALLOW_LEGACY))

		return 1;



	/* Disable MSI during setup in the hardware to erase stale state */

	pci_msi_set_enable(dev, 0);



	struct irq_affinity_desc *masks __free(kfree) =

		affd ? irq_create_affinity_masks(nvec, affd) : NULL;



	msi_lock_descs(&dev->dev);

	ret = msi_setup_msi_desc(dev, nvec, masks);

	if (ret)

		goto unlock;

		return ret;



	/* All MSIs are unmasked by default; mask them all */

	entry = msi_first_desc(&dev->dev, MSI_DESC_ALL);
@@ -394,16 +369,45 @@ static int msi_capability_init(struct pci_dev *dev, int nvec, 


	pcibios_free_irq(dev);

	dev->irq = entry->irq;

	goto unlock;



	return 0;

err:

	pci_msi_unmask(&desc, msi_multi_mask(&desc));

	pci_free_msi_irqs(dev);

unlock:

	msi_unlock_descs(&dev->dev);

	return ret;

}



/**

 * msi_capability_init - configure device's MSI capability structure

 * @dev: pointer to the pci_dev data structure of MSI device function

 * @nvec: number of interrupts to allocate

 * @affd: description of automatic IRQ affinity assignments (may be %NULL)

 *

 * Setup the MSI capability structure of the device with the requested

 * number of interrupts.  A return value of zero indicates the successful

 * setup of an entry with the new MSI IRQ.  A negative return value indicates

 * an error, and a positive return value indicates the number of interrupts

 * which could have been allocated.

 */

static int msi_capability_init(struct pci_dev *dev, int nvec,

			       struct irq_affinity *affd)

{

	/* Reject multi-MSI early on irq domain enabled architectures */

	if (nvec > 1 && !pci_msi_domain_supports(dev, MSI_FLAG_MULTI_PCI_MSI, ALLOW_LEGACY))

		return 1;



	/*

	 * Disable MSI during setup in the hardware, but mark it enabled

	 * so that setup code can evaluate it.

	 */

	pci_msi_set_enable(dev, 0);



	struct irq_affinity_desc *masks __free(kfree) =

		affd ? irq_create_affinity_masks(nvec, affd) : NULL;



	guard(msi_descs_lock)(&dev->dev);

	return __msi_capability_init(dev, nvec, masks);

}



int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,

			   struct irq_affinity *affd)

{